1. Field of the Invention
The present invention relates to a system according to which an information site, provided on a communication network, issues different responses in accordance with the types of the sources of access request transmissions.
2. Discussion of Related Art
Presently, there are many sites on the Internet whereat information on a variety of subjects is available; but not all these sites can be freely accessed, some of them have established membership requirements and limit access to members only, while others grant access only to those users who are willing to pay a browsing fee.
On the Internet to search sites and to efficiently locate and assemble desired information, most users rely on the use of search engines.
FIG. 17 is a diagram of an information search for which a search engine is being employed.
As is shown in FIG. 17, a search engine 210 collects information scattered across the Internet and assembles it to form a URL list, or it initiates a search upon the receipt of a search request from a user terminal 220, to which it transmits the results of the search. For a search, various search methods are used, such as one where a keyword is used or one that is based on parsing performed in accordance with categories.
Further, methods for obtaining information using search engines include one whereby information is registered on a list in accordance with a request from a site, and one that uses a robot search engine to mechanically visit sites and obtain information.
A robot search engine will now be described.
In a robot search engine, software called a robot, a crawler or a spider (hereinafter referred to simply as a robot) uses HTTP to collect search targets, HTML documents, from web servers, and provides a full document, keyword based search service for the collected results. The activities of a typical robot will now be specifically described.
1. Selects one uncollected URL from a URL listing of HTML documents.
2. Transmits an HTTP request to a WWW server in order to obtain an HTML document from the selected URL.
3. Generates for the HTML document, once it has been obtained, an index and an abstract, and either stores them in a storage device, or abandons them.
4. Detects the URL of the HTML document, once it has been obtained, using a hyperlink in the HTML document.
5. Adds the detected URL to the URL list in 1.
6. Returns to 1 if an URL in the URL list has not yet been collected.
This processing is used to control the robot and move it from URL to URL.
Since robot search engines usually do not have the right of access for the sites at which only limited access is permitted, the engines can not enter such sites to retrieve information. Therefore, even when the information required by a user is available at a specific site, so long as only limited access to the site is permitted, attempts by the robot search engine to retrieve information from the site will be rebuffed, and the user in question will not be able to find the site using the robot search engine. This state is shown in FIG. 18.
From the viewpoint of the site, since its URL is not acquired and added to a list of available sites by the robot search engine, the information it can provide will not be fully advertised.
As one method for advertising a site to an audience of unspecified users, the site may be registered on a URL list by a robot search engine and may then be registered with a search engine for the creation, using manpower, of a category list and a home page to be employed as an advertisement, or a banner advertisement may be prepared.
As is described above, when a site on the Internet permits only limited access, a robot search engine that does not have the right of access can not retrieve any information from the site. Thus, the information can not be added to a URL list maintained by the robot search engine, and a user who requires that information will not be able to depend on the robot search engine to search for and acquire the information he or she requires. Therefore, since a site for which only limited access is permitted will not be registered in the URL list of the robot search engine, the existence of the information at the site will not be advertised.
Further, as is described above, in addition to the registration of a site in the URL list of a robot search engine, a method is available whereby human labor is utilized to prepare a URL list and to register a site with a search engine, and another method is available for the setting up of an advertisement home page or the creation of a banner advertisement.
However, robot search engines are widely employed for searching for desired information on the Internet, and using them to register information on URL lists is a very effective advertising means.
Furthermore, for the two advertising methods described above, labor is required to register sites on search engines and to set up homepages and create banner advertisements. And in addition, each time the information available at a site is to be updated, the site issues a notification to that effect and manual labor must be is employed for the updating. But since a robot search engine can automatically access a site and obtain information, the requirement for labor to perform these activities can be eliminated.
Therefore, even though a robot search engine can not acquire information at a site whereat access is limited, metadata (a keyword concerning information) can be provided for the information the robot search engine seeks, and the advertising effects available with the robot search engine can be provided.
Further, if a user, who like a robot search engine does not possess the right of access for a site whereat only limited access is permitted, transmits via a browser an access request to the site, and metadata, such as a message used to describe the information, is provided, even though actual access was not permitted, a beneficial advertisement effect can be expected.
It is, therefore, one object of the present invention to provide metadata, for information that is available at a site whereat only limited access is permitted, upon the receipt by the site of an access request from a robot search engine.
It is another object of the present invention to enable the selective provision of appropriate information, by a site whereat only limited access is permitted, consonant with the access rights of the source of a request for information.